Textured textile material



NOV. 25, 1969 w TURTON ET AL TEXTURED TEXTILE MATERIAL Filed Dec. 13,1967 INVENTORS WALTER TURTON BY CHARLES MAZZQNE ATTORNEY United StatesPatent M ABSTRACT OF THE DISCLOSURE A method and apparatus fortexturizing a textile material wherein the material is mechanicallydeformed to introduce flattened segments of reduced cross-sectionalareas along the length of the yarn whereby a high degree 4 Claims ofresidual shrinkage is maintained in said yarn. This textured yarnexhibits an ability to cause a high degree of stitch distortion when kitin combination with an untextured yarn into a tricot fabric.

This invention relates to the texturizing of thermoplastic textile yarn.One aspect of the present invention relates to a method of processingthermoplastic textile yarn to produce filaments thereof havingvariegated cross-sectional shapes at various intervals along the lengththereof. Another aspect of this invention relates to an apparatus fordistorting a textile yarn at varlous intervals along the length thereof.Yet another aspect of this invention is to produce a texturedthermoplastic synthetic linear high polymer yarn such as polycaproamide(nylon 6) for use in tricot knits, hosiery, wovens, and other types offabrics.

In order to impart certain desirable properties to continuous man-madefilament yarn it has become common practice to texturize or loft thesame. Textured yarn possesses greater bulkiness, better heat insulatingpower and other improved properties while still retaining many of thedesirable characteristics of spun yarn. These properties were achievedby artificially cramping the man-made yarns in order to simulate thebulkiness of certain wool fibers I whose bulkiness is a directconsequence of the kinked or curled character of wool.

One method of considerable commercial significance for producingtextured yarn involves the steps of introducing textile material in asubstantially tensionless state between a set of opposed surfaces whosealternate depressed and raised areas are engaging under an appliedpressure and which engage the material and each other so that thematerial as a result of the tensionless feed zigzags laterally justprior to being gripped and crimped. This method is described in apatent, No. 3,345,718, issued on Oct. 10, 1967, to Hollihan et al. andassigned to J. P. Stevens & Co., Inc.

Another method of considerable commercial significance for producingtextured yarn involves the steps of hot-drawing substantially undrawnthermoplastic continuous filament yarn and immediately thereaftersimultaneously cooling and deforming the yarn by passing same between apair of intermeshing gears.

Another method of considerable commercial importance produces atwist-curled yarn having a lively stretch. Ordinarily, twist-curledtextured yarn is made by a 3- step process. In the first step, the yarnis twisted a desired amount. While in the twisted condition, the yarn isheatset during the second step. That is, the yarn is heated and cooledwhile twisted so as to render the yarn dimenionally stable until againheated to or above the setting temperature. Finally, the yarn isuntwisted. The twist imparted and set in the yarn can be a true twist ora false twist.

Still another method of considerable commercial im- 7 3,479,710 PatentedNov. 25, 1969 ICC portance utilizes the well-known stuffing boxtechnique to induce substantially permanent crimp into the yarn.

The yarn is characterized by sharp elbows between the arms of the crimpsinduced therein.

It has also been known to produce a textured continuous filament yarn byknitting the yarn into fabric, heatsetting the fabric and unravellingthe fabric. In addition, hot gas jet processes are known for texturizingfilament yarn. All of the prior art processes are concerned withimparting a crimp to the yarn being treated.

The subject invention is not concerned with imparting a crimp into theyarn in order to increase its bulkiness but'rather the subject inventionrelates to a process for flattening the yarn at various intervals alongthe length thereof. Moreover the above described prior art methods forproducing crimped' yarn generally result in a product which has amarkedly reduced shrinkage. Since the yarn "is in a relaxed condition,there is nothing to prevent the yarn from shrinking to its fullestextent. Even though the yarn may be subsequently straightened undertension for purposes of packaging or other textile operations, it willnever regain its normal shrinkage. For example, normally drawn nlyon 6has a shrinkage of greater than 8% and usually between 13 and 15%,whereas similar yarn which has been given a heat treatment while relaxedwill have a shrinkage value between 0% and 5%. Yarns that have beensubjected to a knit-set treatment or crimped in a stutfer box are heatedin a substantially tension-free condition to set the crimp in the yarnat which point a very low shrinkage results.

The term shrinkage as used throughout the specification and" claims isintended to mean the actual shortening of the yarn along its actuallength, which phenomena is the result of exposure to heat in a relaxedcondition such as by immersion in boiling water or steam. The termresidual shrinkage employed hereinafter means that after being treatedthe yarn is still able to be further shortened by a subsequent heattreatment.

The term yarn is used to include filaments, tows, slivers, rovings,ribbons, and the like and relates to both monofilament and multifilamentyarns.

One object of this invention is to provide textured yarn having avariegated cross-sectional shape along the length thereof;

Another object of this invention is to vary the bending modulus alongthe length of said yarn;

Another object of this invention is to vary the modulus or flex ofthermoplastic yarns at various intervals along the length thereof;

Yet another object of this invention is to produce a permanentlyintermittently flattened synthetic linear high-polymer yarn that may becollected in package form;

Still another object of the present invention is the production of asynthetic linear high-polymer yarn that possesses at least 5% residualshrinkage.

A still further object of the present invention is to provide a processfor treating synthetic linear high-polymeric yarn to produceintermittent permanent flattening along the length thereof;

A still further object of the present invention is to provide a processfor permanently distorting synthetic linear high-polymeric yarn which isreadily adaptable to existing yarn-treating systems and thereby avoidthe addition of separate operating steps;

A still further object of this invention is the provision of ayarn-treating process which insofar as known functions atrelatively highor low operating speeds although the quality of the yarn improves as thespeed increases and which is not limited in performance to prolongedexposure or dwell time between the yarn and the source of heat at theflattening point;

Other objects and many of the attendant advantages 7,

of this invention will be readily appreciated as the same becomes betterunderstood by reference to the following detailed description which isto be considered in connection with the accompanying drawings wherein:

FIG. 1 is an elevational schematic view of one embodiment of anapparatus according to the invention;

FIG. 2 is an enlarged detail showing the engagement of the rolls fordeforming the textile material according to this invention; and

FIG. 3 is an enlarged view in perspective of segments of textileproducts produced in accordance with the invention.

One of the purposes of producing a yarn, having the deformationdescribed herein at determined intervals is to provide effects infabrics when said yarn is knitted or woven in combination withuntextured yarns. For example, the yarn of the present invention, whencombined with normal yarn in a tricot fabric, produces a pleasingappearance and hand by virtue of the distortion in the fabric surface.These effects in the fabric are caused by a loop distortion producedduring the knitting cycle due to the varying modulus of bending broughtabout by variation in the cross-sectional shape of the textured yarn dueto the flattening of the yarn at regular or irregular intervals.Moreover, a residual shrinkage of at least 5% remaining in the treatedyarn will assist in drawing the companion yarn out of its normal stitchpattern.

In the aforementioned texturizing processes, the textured yarns treatedcannot accomplish this effectively since their shrinkage afterprocessing is very low, namely, from 1 to 2%. The yarn of the presentinvention having both a flattening as opposed to a crimped configurationas well as a high residual shrinkage produces a novel and desirableresult in tricot fabric because of the convolutions of the yarn itselfand also of the distortion of the companion yarn from a normal stitchpattern. The second effect improves as the shrinkage value increases.

Briefly the method of this invention comprises the steps of flattening asoftened thermoplastic yarn to introduce segments of reducedcross-sectional area into the yarn; correlatively controlling thepressures and temperatures to which the yarn is subjected in order topermanently distort the yarn while maintaining a residual shrinkage ofat least 5% in said flattened yarn; and collecting the yarn under acontrolled tension in an orderly manner in compact package form.

According to this invention previously drawn synthetic thermoplasticyarns that have little or no distortions are pressed betWen two surfacesone of which is engraved while the other of which is substantiallysmooth. The yarn is in a softened or plastisized condition topermanently impress into the fibers flattened distortions that arepreferably closely spaced.

A textile product in acordance with this invention can be manufacturedfrom a wide variety of material. For example the textile product may beproteinaceous material, cellulosic matreial, synthetic thermoplasticpolymeric material, thermosetting polymeric material, and the like.Illustrative of such materials are the cellulosic fibers, cellulosicacetate fibers, the polyamides, polyesters, acrylics, and the like.

The preferred form of this invention is to flatten at various intervalsalong the length thereof a continuous monofilament yarn between two niprolls the upper roll of which is serrated around the periphery thereofwhile the lower roll is substantially smooth around the peripherythereof. The faces of the nip rolls are brought into close contact undera pressing relation with the monofilarnent yarn by means of weights,spring pressure, hydraulic pressure, or the like. Moreover the flatteneddistortions present a substantially constant distribution patternthroughout any given length of the monofilament yarn prepared by theprocess of the invention as set forth more fully hereinbelow. However,it is possible to produce flattenings at random along the length of themonofilament yarn in cases where special effects are desired.

The number of flattenings per given linear inch varies inthe range from20 to 62 and preferably from 25 to 45. If the frequency in the number ofdeformations is maintained within this range, a textured yarn isproduced capable when knitted into a tricot fabric with an untexturedyarn of providing the said fabric with a pronounced crepe effect.Moreover it is not intended to confine this invention to lengths of thetextured yarns being left in original form. Deformation of the fullfilament length is permissible so long as there are sutficientvariations, which may vary or not vary in size, in the yarn to effectthe flex modulus thereof. The denier size of the filaments must also becoordinated with the deformation frequency because as the denier size isincreased the number of deformations per unit linear length must also beincreased to provide a suitable textured yarn. In our preferredembodiment we employed 15-denier monofilament yarn.

1 After flattening of the textile material between the surfaces takesplace, the material is removed while being mainatined under controlledtension. The product has a substantial proportion of the flatteningimparted thereto retained substantially permanently.

Generally the fibrous textile material is removed from between theopposed surfaces in a substantially tensionless state. It may be cooledby ambient temperature or it may be positively cooled while beingremoved from between the opposed surfaces.

The material being treated is processed at a temperature and pressure atleast sufficient to permit it to undergo permanent deformation andprevent excessive shrinkage in the fiber. The temperatures and pressuresare correlated to insure that the textured fiber maintains a residualshrinkage of at least 5%.

Where a positive heating step is utilized, the material to be treatedcan be raised to an elevated temperature by any suitable means eitherbefore it passes between the surfaces which deform it or while it isphysically present between the surfaces and undergoing deformation.

The particular temperature employed in the treatment of a particulartextile filamentary material depends upon the characteristics of thematerial itself. For example, certain types of proteinaceous materialsare readily processed at room temperature, that is, at about 20 C. Onthe other hand, a synthetic material such as nylon is processed at atemperature of from between to C. This process can be carried out atlower temperatures than the crimping procedure set forth hereinabove.

In carrying out the process of this invention, the textile materialbeing treated is deformed between the opposed surfaces at a widevariation of applied pressures.

The particular amount of pressure should be at least suflicient toinsure that the material passing between the opposed surfaces is made toproduce flattening at various intervals along the length of the fiber.At the same time the material should not have so much pressure appliedthereto that it is physically damaged by contact between the surfaces.Generally speaking, applied pressures in a range of from 240 to 400pounds per linear inch of the roll is sufficient in most cases toachieve the desired object. On the other hand it is to be noted that themost suitable pressure necessary for processing of any particular fiberis readily determinable and is limited mainly by physical limitations ofthe apparatus or physical limitations of the fibrous material itself.

In carrying out the practice of the invention it should also be notedthat positive means for setting the material being treated arepreferably, although not necessarily, utilized. As pointed outhereinabove such means may include raising the fibrous material to anelevated temperature but also may include pretreatment with a chemicalsetting agent or the like.

Any suitable chemical setting agent for the particular fiibrous materialbeing processed can be used. Examples of suitable chemical settingagents for keratin based fibers are reducing agents, alkaline reducingagents, thiols such as thioglycollic acid and saturated steam atelevated pressures. For other proteinaceous fibers such as silk, hightemperature steam and any of the conventional tanning chemicals as wellas formaldehyde may be used. For cellulosics, the setting agents couldbe drawn from any of the chemical groups such as formaldehyde, ureaformaldehyde, melamine formaldehyde, and other such thermosetting agentsor chemicals. In general any chemical which is able to supply permanentcrosslinking either by covalent or by any other type of permanentbonding is suitable. Thermosplastic fibers may be presoftened either byheat or the use of volatile plastisizers which would be evaporated offduring the setting operation.

With ones attention now being directed to the drawings, furtherelucidation of the present invention will be given. There is shown inFIG, 1 an apparatus generally designated as which is suitable fortreatment of textile material, in this case illustrated as fibers, inaccordance with the invention. In this embodiment there is depicted abeam 11 on which is wound a large number of ends of a monofilamenttextile material, in this case illustrated as fibers, in accordance withthe invention. Beam 11 is supported by journal means, not shown, and isfree-running but provided with a friction drag or other suitable deviceto provide uniform tension in the fibrous textile material on the beam.

The fibrous textile material 13 passes through a reed 15 supported bymeans not shown.

The material 13 then passes between a set of grooved surfacesillustrated as a pair of rolls 19 and 21. Although only two surfaces areillustrated in this embodiment, the number of opposed surfaces may begreater than two. At least one of the rolls, preferably the one placedin the upper position 19, is provided with an engraved surface having asurface configuration which is designed to impart a flattening atvarious intervals along the length of the textile material 13 passingbetween the two surfaces. In order to obtain a flattening as opposed toa crimping effect, it is critical that the bottom roll 21 has a smoothunembossed surface. The nature of the composition of rolls 19 and 21 isnot critical but should be of a material that can withstand heat andpressure in order to prevent either of them from wearing excessively.

Drive roll 19 is rotated by means not shown and roll 21 is driven as aresult of the frictional force resulting from the pressure contact withroll 19.

One or both of the rolls may be heated by conventional means such as oilcirculating inside the roll or rolls to facilitate the deformation ofthe material 13 between the rolls.

The take-up assembly, generally designated as 23 comprises rolls 25 and27 and is capable of maintaining the fibrous textile material 13 undercontrolled tension until it is cooled sufiiciently to retainsubstantially permanently the flattening configuration imparted thereto.Both rolls 25 and 27 are driven by means not shown. Any suitable take-upassembly may be used for this purpose; moreover the take-up rolls maycomprise a set of rolls which can be greater than two in number ifdesirable. In addition it is to be noted that either one or both of thetakeup rolls 25 and 27 can be utilized to provide positive cooling meansfor cooling the textile material being processed. It should be furtherunderstood, however, that the textile material being treated may becooled sufiiciently to achieve substantially permanent configuration ofthe deformation therein solely as a result of ambient heat exchange.Therefore rolls 25 and 27 would not have to be adapted for coolingpurposes.

Alternative methods of cooling are also possible such as passing thematerial through an atmosphere which is maintained at a low ambienttemperature. Regardless of the particular method of cooling utilized,the cooling should be accomplished before the yarns are exposed toforces which would tend to remove the flattening imparted thereby byrolls 19 and 21.

The textured yarn is wound onto beam 30 after passing from the take-upassembly 23.

With reference to FIG. 2, grooves 29 in roll 19 are helical and are atan angle of approximately 25 degrees with the axis of roll 19. Thegrooves 29 are separated by land areas 32. The helical configuration isused to avoid pattern repeats in a fabric woven or knitted from materialprocessed in accordance with the invention. However, for the purposes ofthis invention, it is to be appreciated that the angle of the grooves isnot critical and that in fact the engraved roll may have grooves whichare vertical to the horizontal.

Since this is not a crimping operation but rather a flattening of thefiber at various intervals, the depth of grooves 29 are dependent inpart on the spacing thereof. That is to say, the maximum depth islimited by the requisite land area configuration needed to withstand thepressures necessary for the flattening operation. The permissible depthof the grooves may range from 0.004 inch to about 0.010 inch. Naturallyit is desirable to remove any and all sharp edges so as to avoid anypossibility of cutting the yarn being treated.

With respect to the selection of diameters for rolls 19 and 21, theembodiment shown in FIG. 1 depicts substantially equal diameters.However, the bottom roll can be of larger diameter than the top roll.

BIG. 3 shows a yarn 31 which has been texturized according to theprocess described hereinabove.

The following examples are offered to illustrate the principle of thisinvention. Nylon 66 yarn (polymer of adipic acid andhexamethylenediamine) was treated according to the teaching of thisinvention.

EXAMPLE 1 An apparatus similar to that shown in FIG. 1 was used, withroll 19 having 62 grooves per inch, equally spaced, and positioned at:an angle of 26 to the axis of rotation of the rolls. The grooves inroll 19 have a depth of 0.008 inch. There was no cooling other thannatural ambient heat exchange. Roll 19 was composed of steel and roll 21was composed of nylon.

A sheet of 15/1 polyhexamethylene adipamide (type 66 nylon) containing588 ends was flattened at a linear speed through rolls 19 and 21 at feetper minute.

It was found that suitably flattened yarn was produced with a pressureof pounds per linear inch when roll 19 was heated to 370 'F. This yarnretained 5.5% of its residual shrinkage.

This textured yarn having 28 needles per inch when knit in a tricotmachine along with an untextured 20/7 nylon 66 yarn produced a tricotfabric exhibiting a pleasing appearance and hand by virtue of thedistortion of the stitch formation.

EXAMPLE 2 An apparatus similar to that shown in FIG. 1 was used, withroll 19 having 40 grooves per inch, equally spaced, and positioned at anangle of 45 to the axis of rotation of the rolls. The grooves 29 in roll19 had a depth of 0.008 inch. There was no cooling other than naturalambient heat exchange. Rolls 19 and 21 were composed of steel and nylonrespectively.

A single end type 66 nylon 15/1 monofilament yarn was flattened at alinear speed through rolls 19 and 21 at 150 feet per minute.

It was found that suitably flattened yarn was produced with a pressureof 180 pounds per linear inch when roll 19 was heated to 370 F. Thisyarn retained 5.5% of its residual shrinkage.

This textured yarn when knit as in Example 1 produced a tricot fabricexhibiting a pleasing appearance and hand by virtue of the distortion ofthe stitch formation.

See footnote 1 at bottom of Column 7.

7 EXAMPLE 3 An apparatus similar to that shown in FIG. 1 also spaced andpositioned at an angle of 45 to the axis of rotation of the rolls. Thegrooves 29 in roll 19 had a depth of 0.011 inch. There was no coolingother than natural ambient heat exchange. Rolls 19 and 21 were composedof steel and nylon respectively,

A single end type 66 nylon /1 monofilament yarn was flattened at alinear speed through rolls 19 and 21 at 150 feet per minute.

It was found that suitably flattened yarn was produced with a pressureof 120 pounds per linear inch when roll 19 was heated to 290 F. Thisyarn retained 8.0% of its residual shrinkage.

EXAMPLE 4 An apparatus similar to that shown in FIG. 1 also heated withroll 19 having 25 grooves per inch, equally spaced and positioned at anangle of to the axis of rotation of the rolls. The grooves 29 in roll 19had a depth of 0.011 inch. There was no cooling other than naturalambient heat exchange. Rolls 19 and 21 were composed of steel and nylonrespectively.

An apparatus similar to that shown in FIG. 1 also heated with roll 19having 25 grooves per inch, equally spaced and positioned at an angle of45 to the axis of rotation of the rolls. The grooves 29 in roll 19 had adepth of 0.011 inch. There was no cooling other than natural ambientheat exchange. Rolls 19 and 21 were composed of steel and nylonrespectively.

A single end type 66 nylon 15/1 monofilament yarn was flattened at alinear speed through rolls 19 and 21 at 150 feet per minute.

It was found that suitably flattened yarn was produced with a pressureof 120 pounds per linear inch when roll 19 was heated to 365 F. Thisyarn retained 5.0% of its residual shrinkage.

1 Single end Shrinkage SCOPE This method has been developed by J. P.Stevens to test the shrinkage of an individual end of filament yarnremoved from a woven or knitted fabric.

PROCEDURE (1) Loops to cm. of yarn. Tie ends together.

(2) Hang yarn on vertical meter stick (attached to Wall) that has a pegat top which serves as a hook for yarn.

(3) Attach .1 gm./denler 2 (number of ends in loop) to yarn. Recordreading A.

(4) Remove weight and boil oft (210212 F.) in cheese cloth. Time 30minutes.

(5) Dry for two hours in a steam heated oven (closed c011) -120 F.

(6) Hang on vertical meter stick and repeat Step 3. Record as length B.

Calculation: A

The permanency of the distortions in the yarn flattened according to theconditions described in Examples 3, 4 and 5 was not aflected. I

Obviously many modifications and variations of the present invention arepossible in the light of the above teachings. It is therefore to beunderstood that Within the scope of the appended claims the inventionmay be practiced otherwise than asspecifically described herein.

What is claimed is:

1. A process for texturizing a monofilament thermoplastic yarncomprising the steps of flattening a softened previously drawnmonofilament thermoplastic yarn to introduce segments of reducedcross-sectional areas into the yarn whereby said yarn exhibits avariation in bending modulus along the length thereof; correlativelycontrolling the pressures and temperatures to which the yarn issubjected in order to effect permanent distortion of the yarn whilemaintaining a residual shrinkage of at least 5% in said flattened yarn,and collecting the textured yarn under a controlled tension so as toeliminate any further drawing thereof in an orderly manner in compactpackage form, whereby a yarn having varigated cross-sectional shapes ofuniform consistency located at predetermined intervals along the lengththereof is produced.

2. A process according to claim 1 wherein the number of flattenings pergiven linear inch varies in the range from 20 to 62.

3. A process according to claim 1 wherein the yarn is treated at atemperature ranging from to 370 F.

4. A process according to claim 1 wherein a polyhexamethylene adipamidemonofilament yarn is texturized.

References Cited UNITED STATES PATENTS 2,044,135 6/ 1936 Taylor.

2,975,474 3/1961 Smith.

3,069,726 12/1962 Adams.

3,116,197 12/1963 Kasey.

FOREIGN PATENTS 1,462,511 11/ 1966 France.

JAMES KEE CHI, Primary Examiner US. Cl. X.R.

